The present invention relates to porous absorbent materials for absorbing oils and fats in water.
Split crude oil or a variety of waste oils contained in waste waters discharged from petrochemical plants, petroleum refineries, iron works, shipbuilding yards and other sources float or are contained in a state of emulsion in fresh or sea water, and constitute pollutants of rivers, streams and oceans. Furthermore, such oily substances in some cases tend to cohere and precipitate or settle after being maintained in the floating condition for a certain period of time. They thus exert adverse effects on organisms living on the bottoms of rivers and the sea, while they continue to be kept in the sediments semipermanently. In view of the above, development of appropriate treatment processes for oils and fats in water is urgently needed.
Under these circumstances, it is deemed the most effective to eliminate such oils and fats while they are in the hydrated condition before they cohere and settle. A great number of processes for eliminating oils and fats have been conventionally developed in the past.
By way of example, a process for eliminating oils and fats floating over the surface of the sea water has actually been adopted for commercial use which comprises allowing mat-shaped, fibrous materials to float on the surface of the sea water, contacting the oils and fats to permit adequate impregnation of the mats therewith. The mats exhibit a certain degree of adsorption for oils and fats and are composed of chemical fibers. However, the process has certain disadvantages once the mats have adsorbed the oils and fats, such as release of adsorbed oils and fats from the mats, evolution of toxic gases during incineration of such mats and damaging of an incinerator due to higher burning temperatures while incinerating the mats.
The porous adsorbent material for oils and fats according to the present invention has been developed with the specific aim of solving the above-mentioned problems so far encountered. Additionally, the present invention is less expensive and is easier to handle.